Counterbalance weights



March 17,1910 BQSCHRQER Em 3,501,021

COUNTERBALANCE WEIGHTS Filed Dec. 20, 1967 I 3 Sheets-Sheet 1 Inventor: fine/mm Dav .S'CHAE/tk do Aw 880w Alton-my:

March 17, 1970 a. o. SCHREIER :rm. ,0 3,501,021

COUNTERBALANCE WEIGHTS Filed Dec. 20, 1967 3 Sheets-Sheet z Inventor: 8:.eA me Dar James/:1? da /v .d/emu/v y rm A Home ys March 17, 1970 a. D.SCHREIER YETAL 3,501,021

COUKTERBALANCE WEIGHTS Filed Dec. 20. 1967 3 Sheets-Sheet 5 lnvenlor: dim/nu) Dav Selves/1e Jamv flew/v A Home ys.

United States Patent 3,501,021 COUNTERBALANCE WEIGHTS Bernard Dov Schreier and John Brown, both of 233 Regents Park Road, London, N. 3, England Filed Dec. 20, 1967, Ser. No. 692,211 Claims priority, application Great Britain, Dec. 22, 1966, 57,473/66; Feb. 3, 1967, 5,367/67 Int. Cl. B66c 23/72 US. Cl. 212-49 Claims ABSTRACT OF THE DISCLOSURE A weight-lifting and lowering vehicle, e.g. for pipe-laying, has a lufiing boom on one side of the vehicle, and on the opposite side of the vehicle counterbalance means comprising a frame pivoted at its lower end to the vehicle, a weight mounted on, and movable longitudinally of, the frame, and separate hydraulic means respectively for varying the angle of the counterbalance frame, and for moving said weight along the frame.

This invention relates to counterbalance weights, and more especially to such weights as used upon contractors equipment intended for heavy work, e.g. for excavating, pipe lifting and laying, or other lifting and lowering duties on a building site or a road.

Although applicable to other forms of equipment, the invention will be disclosed in the form suitable for use on pipe laying equipment, which normally comprises a tractor having derrick-like lifting means adapted to be lowered in order to extend outwards from, and over, one side of the tractor, in order to lift, carry and/or lay a pipe in a trench beside which the vehicle is operating. When the crane device is projecting to one side of the vehicle and carrying a heavy load the vehicle is liable to overturn, and in order to safeguard against such an event it is common practice to provide at the opposite side of the vehicle a heavy weight which can be moved away from, or towards, the side of the vehicle in order to provide a torque counterbalancing the torque due to the load, tending to tip up the vehicle.

The invention consists in a counterbalancing device comprising a weight movably supported on a pivoted arm, and means for varying the position of the weight on the arm when the arm is swung about its pivot to modify the counterbalance torque provided.

Movement of the weight in relation to the arm may be effected by means of a flexible connection, such as a cable, attached to it or by hydraulic means. In the former case the weight may comprise a slide member (cg. a platform), movable in guides in the arm. The cable may run on a pulley mounted in the arm, and the other end of the cable may be secured to a fixed part of the equipment. Thus as the arm swung about its pivot the cable runs on the pulley, and draws up or lowers the slide member in relation to the arm. In the latter case the support may also be swung between retracted and extended positions by hydraulic means. By retracted and extended positions are meant positions in which respectively the counterbalance weight exercises little or no torque, and a maximum torque, tending to overturn the equipment.

The invention will be clearly understood from the following description of one form (given however, merely by way of example) which it may assume, and this description will be more readily followed by reference to the accompanying drawings wherein FIGURE 1 represents in front elevation counterbalance means in accordance with the invention;

FIGURES 2 and 3 represent respectively in front and ice side elevation counterbalance means in accordance with the invention.

Referring to FIGURE 1 of the aforesaid drawings, counterbalance means in accordance with the invention are shown as fitted to a tractor vehicle (suitable, for example, for use in pipe-laying), of which a track 1 and a fixed part 2 at one side of the vehicle are shown. Lifting and lowering means are mounted on the vehicle and adapted to be swung out from the opposite side of the vehicle in order to take up a load, as a result of which a torque is applied to the vehicle tending to tip over the vehicle on its side.

In the form of counterbalance means according to the invention illustrated in FIGURE 1, and intended to apply an opposite torque to the vehicle (whereby to prevent overturning) an upstanding arm, beam or frame 3 (hereinafter referred to as an arm) is pivoted at its lower end 4 to a support 5 projecting from the side of the vehicle. A hydraulic piston and cylinder device 6 between the arm 3 and the vehicle enables the arm to be swung out or drawn back, in relation to the vehicle, as desired.

A bracket-shaped platform 8 is fitted with guiding and supporting rollers 9 which run in slotted or grooved ways in the arm 3. A pulley 10 is rotatably mounted in the arm 3 at its upper end. A cable 11 secured by one end to the bracket platform 8 runs over the pulley 10 and at its other end is attached at 12 to a fixed part 2 of the vehicle. A heavy mass 13 is mounted on and secured to the platform 8 (but may be interchangeable with other blocks of different sizes and weights).

In using the above-described means, when the vehicle is subject to a torque tending to overturn it, due to the work load with which it is dealing (at the remote side of the vehicle shown in the drawing) the arm 3 is swung outwards about the pivot 4, by the hydraulic device 6, to any desired position, such as shown in chain line in the drawing. Since the inner end of the cable 11 is fixed at 12 this swinging of the arm 3 causes the cable to run over the pulley 10, and the slide 8, with its mass 13, is drawn upwards towards the upper end of the arm 3. Thus not only does the swinging of the arm 3 provide a counter-torque by merely swinging the mass 13 outwards from the vehicle, but it increases the torque thus set up by lifting the mass 13 to a higher position along it length, thus carrying it to a greater distance from the side of the vehicle. By this means as a result of a comparatively limited angular movement of the arm 3, a wide range of torque values is available to counterbalance loads of widely different values.

In FIGURES 2 and 3 of the aforesaid drawings representing a modified embodiment of the invention, can be seen one side track 21, a forward cross-member 22, and the engine 23 of a vehicle. An inverted U-shaped frame 24 is mounted on a cross-member 25 pivoted at 26 to the side of the vehicle chassis. Two spaced hydraulic rams 27 connected between a cross bar 28 of the frame 24, and the side of the vehicle, are adapted when operated to swing the frame 24 between a retracted position substantially upright and over the vehicle, (shown in full lines in FIGURE 3), and an outwardly extended position (shown in dotted lines).

A weight 29 extending transversely of the upright limbs of the frame 24 is mounted on hydraulic rams 30 and slidable on the outer sides of the limbs of the frame. Thus when the rams 30 are actuated the weight 29 is lifted towards the upper end of the frame 24, and if this frame is in (or is moved to) an extended position the weight applies a substantial torque to the vehicle to counterbalance a torque derived from a crane or like lifting means extending from the opposite side of the vehicle and lifting a load, e.g. a pipe.

From the above description it will be seen that the invention provides a simple and easily controlled counterbalancing arrangement, but it should be understood that the invention is not limited solely to the details of the form described above, which may be modified, in order to meet various conditions and requirements encountered without departing from the scope of the invention.

What we claim is:

1. Crane-like lifting and lowering means provided with a counter-balance device comprising a boom mounted for pivotal movement between a substantially vertical position, and a position inclined to the vertical, a weight mounted on, and movable along said boom, a first hydraulic means adapted, when actuated, to swing said boom about its pivot irrespective of the position of said weight on said boom, and a second hydraulic means adapted to move said weight along said boom irrespective of the in.- clination of said boom.

2. Crane-like lifting means with a counterbalance device according to claim 1 wherein the boom is an inverted U-shaped frame mounted on a pivot adjacent to the lower ends of its legs, and the weight is carried by a support extending transversely of the legs of said frame, and movable longitudinally along said legs.

3. Chane-like lifting means with a counterbalance device according to claim 1 wherein said weight is supported on a movable platform, and said second hydraulic means comprise a hydraulic ram operatively connected to said platform.

4. Crane-like lifting means with a counterbalance device according to claim 1 wherein said boom comprises a U-shaped frame, and said first hydraulic means comprise ram means operatively connected to a side-limb of said frame.

5. A vehicle comprising a weight-lifting crane on one side of said vehicle, and on the other side of said vehicle a counterbalance device comprising a frame pivoted at its lower end of said vehicle, and movable about its pivot between substantially vertical, and outwardly inclined, positions, a weight mounted on, and movable longitudinally of, said frame, first hydraulic means connected between said vehicle and said frame, adapted when actuated to swing said frame about its pivot, and second hydraulic means connected between said weight and said frame, adapted when actuated to displace said weight along said frame.

References Cited UNITED STATES PATENTS 701,887 6/1902 Jackson. 1,010,766 12/1911 Hulett 214-127 X 1,195,058 8/1916 Marfell 212-49 2,130,487 9/1938 Foley 212-49 FOREIGN PATENTS 544,699 8/1957 Oanada.

1,773 6/ 1862 Great Britain.

HUGO O. SCHULZ, Primary Examiner US. Cl. X.R. 214-142 

